Understanding Your Car’s Locking Mechanism

Every vehicle has a central locking system that is meant to keep unauthorized individuals out of your car, while allowing you to open the doors, the boot and drive it. Modern locking systems consist of manual or remote keyless mechanism, or a combination of the two. While the manual system allows you to centrally lock all the doors and the tailgate using a button on the driver’s door, a remote keyless system works similarly to a television remote – you can press a button to allow access to the car without the need of a key.

What is Central Locking?

Central locking is not straightforward either, as there are three subsystems that comprise this electromechanical system.

The remote controller is the small, handheld, battery operated device that transmits radio frequency or infrared signals to the car’s computer or electronic control module (ECM).

The electronic control module (ECM) processes the signal, and based on the amount of power polarity, it supplies signals to the motors or solenoids of the different actuators.

The actuators make the locking or unlocking action happen. They are located in the doors, and can be motor based or solenoid based. Solenoids are a type of electromagnetic switch that locks doors when hit by one type of current from the ECM, and unlocks it when the current comes from the opposite direction. DC motors work in a similar fashion.

In order to send signals to the actuators, we use a transponder, which is usually located inside the key bow. The car’s immobiliser can identify whether the signal is coming from the correct key using the transponder code when the key approaches the car.

In smaller cars, all the conventional functions of keys are replaced by infrared remote controls, which can read instructions from a range of approximately 15 meters. The remote signal transmitter will send a signal to the receiver, which generally controls a variety of functions. These remotes rely on a direct line of “vision” between the receiver and the transmitter. More modern cars however, rely on wireless radio frequency transmission of up to 100 m by remote control.

Some cars have locks on their fuel filler caps, while others don’t. It is important for the fuel filler cap to seal the fuel tank securely. Most newer vehicles have fuel filler caps that are operated via the central locking system.

Certain insurance companies require that cars have steering locks in order to help prevent theft. The steering lock can be locked mechanically, or by having it incorporated via the electrical central locking system.

Central locking systems help to increase your safety and the security of the vehicle. It can help protect your vehicle against theft by deterring would-be car thieves. Most systems use integrated controls, such as lighting elements on the dash panel, or beeping when the doors are not closed properly, or when the driver is not wearing a safety belt to keep you safer on the road.